Someone ass-grinding you while you're trying to aim is one of the most heinous forms of dickery in the game. It either demonstrates a complete lack of understanding of tank mechanics (kid playing on dad's account?) or an intentional desire to be an asshole.
Rather than take the loss for the emotional win, I'll just leave the battle (can I wedge the asshole up against a rock first?) and go play another tank. I don't have time for that shit.